CS 143A - Principles of Operating Systems
|
|
- Josephine Wilson
- 5 years ago
- Views:
Transcription
1 CS 143A - Principles of Operating Systems Operating Systems - Review of content from midterm to final Prof. Nalini Venkatasubramanian nalini@ics.uci.edu
2 Deadlocks System Model Resource allocation graph, claim graph (for avoidance) Deadlock Characterization Conditions for deadlock - mutual exclusion, hold and wait, no preemption, circular wait. Methods for handling deadlocks Deadlock Prevention Deadlock Avoidance Deadlock Detection Recovery from Deadlock Combined Approach to Deadlock Handling 2
3 Deadlock Prevention If any one of the conditions for deadlock (with reusable resources) is denied, deadlock is impossible. Restrain ways in which requests can be made Mutual Exclusion - cannot deny (important) Hold and Wait - guarantee that when a process requests a resource, it does not hold other resources. No Preemption If a process that is holding some resources requests another resource that cannot be immediately allocated to it, the process releases the resources currently being held. Circular Wait Impose a total ordering of all resource types. 3
4 Deadlock Avoidance Requires that the system has some additional a priori information available. Simplest and most useful model requires that each process declare the maximum number of resources of each type that it may need. Computation of Safe State When a process requests an available resource, system must decide if immediate allocation leaves the system in a safe state. Sequence <P1, P2, Pn> is safe, if for each Pi, the resources that Pi can still request can be satisfied by currently available resources + resources held by Pj with j<i. Safe state - no deadlocks, unsafe state - possibility of deadlocks Avoidance - system will never reach unsafe state. 4
5 Algorithms for Deadlock Avoidance Resource allocation graph algorithm only one instance of each resource type Banker s algorithm Used for multiple instances of each resource type. Data structures required Available, Max, Allocation, Need Safety algorithm resource request algorithm for a process. 5
6 Memory Management Main Memory is an array of addressable words or bytes that is quickly accessible. Main Memory is volatile. OS is responsible for: Allocate and deallocate memory to processes. Managing multiple processes within memory - keep track of which parts of memory are used by which processes. Manage the sharing of memory between processes. Determining which processes to load when memory becomes available. 6
7 Binding of instructions and data to memory Address binding of instructions and data to memory addresses can happen at three different stages. Compile time, Load time, Execution time Other techniques for better memory utilization Dynamic Loading - Routine is not loaded until it is called. Dynamic Linking - Linking postponed until execution time Overlays - Keep in memory only those instructions and data that are needed at any given time Swapping - A process can be swapped temporarily out of memory to a backing store and then brought back into memory for continued execution MMU - Memory Management Unit Hardware device that maps virtual to physical address. 7
8 Contiguous Allocation Divides Main memory usually into two partitions Resident Operating System, usually held in low memory with interrupt vector and User processes held in high memory. Single partition allocation Relocation register scheme used to protect user processes from each other, and from changing OS code and data Multiple partition allocation holes of various sizes are scattered throughout memory. When a process arrives, it is allocated memory from a hole large enough to accommodate it. Variation: Fixed partition allocation 8
9 Dynamic Storage Allocation Problem How to satisfy a request of size n from a list of free holes. First-fit Best-fit Worst-fit Fragmentation External fragmentation total memory space exists to satisfy a request, but it is not contiguous. Internal fragmentation allocated memory may be slightly larger than requested memory; this size difference is memory internal to a partition, but not being used. Reduce external fragmentation by compaction 9
10 Paging Logical address space of a process can be noncontiguous; process is allocated physical memory wherever the latter is available. Divide physical memory into fixed size blocks called frames size is power of 2, 512 bytes - 8K Divide logical memory into same size blocks called pages. Keep track of all free frames. To run a program of size n pages, find n free frames and load program. Set up a page table to translate logical to physical addresses. Note:: Internal Fragmentation possible!! 10
11 Page Table Implementation Page table is kept in main memory Page-table base register (PTBR) points to the page table. Page-table length register (PTLR) indicates the size of page table. Every data/instruction access requires 2 memory accesses. One for page table, one for data/instruction Two-memory access problem solved by use of special fastlookup hardware cache (i.e. cache page table in registers) associative registers or translation look-aside buffers (TLBs) 11
12 Paging Methods Multilevel Paging Each level is a separate table in memory converting a logical address to a physical one may take 4 or more memory accesses. Caching can help performance remain reasonable. Inverted Page Tables One entry for each real page of memory. Entry consists of virtual address of page in real memory with information about process that owns page. Shared Pages Code and data can be shared among processes. Reentrant (non self-modifying) code can be shared. Map them into pages with common page frame mappings 12
13 Segmentation Memory Management Scheme that supports user view of memory. A program is a collection of segments. A segment is a logical unit such as main program, procedure, function local variables, global variables,common block stack, symbol table, arrays Protect each entity independently Allow each segment to grow independently Share each segment independently 13
14 Segmented Paged Memory Segment-table entry contains not the base address of the segment, but the base address of a page table for this segment. Overcomes external fragmentation problem of segmented memory. Paging also makes allocation simpler; time to search for a suitable segment (using best-fit etc.) reduced. Introduces some internal fragmentation and table space overhead. Multics - single level page table IBM OS/2 - OS on top of Intel 386 uses a two level paging scheme 14
15 Virtual Memory Virtual Memory Separation of user logical memory from physical memory. Only PART of the program needs to be in memory for execution. Logical address space can therefore be much larger than physical address space. Need to allow pages to be swapped in and out. Virtual Memory can be implemented via Paging Segmentation 15
16 Demand Paging Bring a page into memory only when it is needed. Less I/O needed Less Memory needed Faster response More users The first reference to a page will trap to OS with a page fault. OS looks at another table to decide Invalid reference - abort Just not in memory. 16
17 Page Replacement Prevent over-allocation of memory by modifying page fault service routine to include page replacement. Use modify(dirty) bit to reduce overhead of page transfers - only modified pages are written to disk. Page replacement large virtual memory can be provided on a smaller physical memory. 17
18 Page Replacement Strategies The Principle of Optimality Replace the page that will not be used again the farthest time into the future. Random Page Replacement Choose a page randomly FIFO - First in First Out Replace the page that has been in memory the longest. LRU - Least Recently Used Replace the page that has not been used for the longest time. LRU Approximation Algorithms - reference bit, second-chance etc. LFU/MFU - Least/Most Frequently Used Replace the page that is used least/most often. 18
19 Allocation of Frames Single user case is simple User is allocated any free frame Problem: Demand paging + multiprogramming Each process needs minimum number of pages based on instruction set architecture. Two major allocation schemes: Fixed allocation - (1) equal allocation (2) Proportional allocation. Priority allocation - May want to give high priority process more memory than low priority process. 19
20 Thrashing If a process does not have enough pages, the page-fault rate is very high. This leads to: low CPU utilization. OS thinks that it needs to increase the degree of multiprogramming Another process is added to the system. System throughput plunges... Thrashing A process is busy swapping pages in and out. In other words, a process is spending more time paging than executing. 20
21 Working Set Model Δ working-set window a fixed number of page references, e.g. 10,000 instructions WSSj (working set size of process Pj) - total number of pages referenced in the most recent Δ (varies in time) If Δ too small, will not encompass entire locality. If Δ too large, will encompass several localities. If Δ =, will encompass entire program. D = WSSj total demand frames If D > m (number of available frames) thrashing Policy: If D > m, then suspend one of the processes. 21
22 File System Management File is a collection of related information defined by creator - represents programs and data. OS is responsible for File creation and deletion Directory creation and deletion Supporting primitives for file/directory manipulation. Mapping files to disks (secondary storage). Backup files on archival media (tapes). 22
23 File Concept Contiguous logical address space OS abstracts from the physical properties of its storage device to define a logical storage unit called file. OS maps files to physical devices. Types Data, Program, Documents File Attributes Name, type, location, size, protection etc. File Operations Create, read, write, reposition, delete etc.. 23
24 Directory Structure Number of files on a system can be extensive Hold information about files within partitions called directories. Device Directory: A collection of nodes containing information about all files on a partition. Both the directory structure and files reside on disk. Backups of these two structures are kept on tapes. Operations on a directory create a file, delete a file, search for a file, list directory etc. 24
25 Logical Directory Organization Goals - Efficiency, Naming, grouping Single Level Directories Single level for all users, naming and grouping problem Two Level Directories first level - user directories, second level - user files Tree Structured Directories arbitrary depth of directories, leaf nodes are files Acyclic Graph Directories allows sharing, implementation by links or shared files General Graph Directories allow cycles - must be careful during traversal and deletion. 25
26 File Protection - Access lists and groups Associate each file/directory with access list Problem - length of access list.. Solution - condensed version of list Mode of access: read, write, execute Three classes of users owner access - user who created the file groups access - set of users who are sharing the file and need similar access public access - all other users In UNIX, 3 fields of length 3 bits are used. Fields are user, group, others(u,g,o), Bits are read, write, execute (r,w,x). E.g. chmod go+rw file, chmod 761 game 26
27 File-System Implementation File System Structure File System resides on secondary storage (disks).to improve I/ O efficiency, I/O transfers between memory and disk are performed in blocks. Read/Write/Modify/Access each block on disk. File System Mounting - File System must be mounted before it can be available to process on the system. The OS is given the name of the device and the mount point. Allocation Methods Contiguous Linked Indexed 27
28 Allocation of Disk Space Low level access methods depend upon the disk allocation scheme used to store file data Contiguous Allocation Each file occupies a set of contiguous blocks on the disk. Dynamic storage allocation problem. Files cannot grow. Linked List Allocation Each file is a linked list of disk blocks. Blocks may be scattered anywhere on the disk. Not suited for random access. Variation - FILE ALLOCATION TABLE (FAT) mechanisms Indexed Allocation Brings all pointers together into the index block. Need index table. Can link blocks of indexes to form multilevel indexes. 28
Module 8: Memory Management
Module 8: Memory Management Background Logical versus Physical Address Space Swapping Contiguous Allocation Paging Segmentation Segmentation with Paging Operating System Concepts 8.1 Silberschatz and Galvin
More informationVirtual Memory. CSCI 315 Operating Systems Design Department of Computer Science
Virtual Memory CSCI 315 Operating Systems Design Department of Computer Science Notice: The slides for this lecture have been largely based on those from an earlier edition of the course text Operating
More informationUnit-03 Deadlock and Memory Management Unit-03/Lecture-01
1 Unit-03 Deadlock and Memory Management Unit-03/Lecture-01 The Deadlock Problem 1. A set of blocked processes each holding a resource and waiting to acquire a resource held by another process in the set.
More informationLogical versus Physical Address Space
CHAPTER 8: MEMORY MANAGEMENT Background Logical versus Physical Address Space Swapping Contiguous Allocation Paging Segmentation Segmentation with Paging Operating System Concepts, Addison-Wesley 1994
More informationCS370 Operating Systems
CS370 Operating Systems Colorado State University Yashwant K Malaiya Fall 2016 Lecture 42 Virtualization Review Slides based on Various sources 1 1 FAQ For VMM, is the CPU scheduling just like a single
More informationModule 8: Memory Management
Module 8: Memory Management Background Logical versus Physical Address Space Swapping Contiguous Allocation Paging Segmentation Segmentation with Paging 8.1 Background Program must be brought into memory
More informationModule 9: Memory Management. Background. Binding of Instructions and Data to Memory
Module 9: Memory Management Background Logical versus Physical Address Space Swapping Contiguous Allocation Paging Segmentation Segmentation with Paging 9.1 Background Program must be brought into memory
More informationChapter 8: Memory Management. Operating System Concepts with Java 8 th Edition
Chapter 8: Memory Management 8.1 Silberschatz, Galvin and Gagne 2009 Background Program must be brought (from disk) into memory and placed within a process for it to be run Main memory and registers are
More informationMemory Management Cache Base and Limit Registers base limit Binding of Instructions and Data to Memory Compile time absolute code Load time
Memory Management To provide a detailed description of various ways of organizing memory hardware To discuss various memory-management techniques, including paging and segmentation To provide a detailed
More informationChapter 9: Memory Management. Background
1 Chapter 9: Memory Management Background Swapping Contiguous Allocation Paging Segmentation Segmentation with Paging 9.1 Background Program must be brought into memory and placed within a process for
More informationFall COMP3511 Review
Outline Fall 2015 - COMP3511 Review Monitor Deadlock and Banker Algorithm Paging and Segmentation Page Replacement Algorithms and Working-set Model File Allocation Disk Scheduling Review.2 Monitors Condition
More informationPart Three - Memory Management. Chapter 8: Memory-Management Strategies
Part Three - Memory Management Chapter 8: Memory-Management Strategies Chapter 8: Memory-Management Strategies 8.1 Background 8.2 Swapping 8.3 Contiguous Memory Allocation 8.4 Segmentation 8.5 Paging 8.6
More informationMemory Management. CSCI 315 Operating Systems Design Department of Computer Science
Memory Management CSCI 315 Operating Systems Design Department of Computer Science Notice: The slides for this lecture are based on those from Operating Systems Concepts, 9th ed., by Silberschatz, Galvin,
More information8.1 Background. Part Four - Memory Management. Chapter 8: Memory-Management Management Strategies. Chapter 8: Memory Management
Part Four - Memory Management 8.1 Background Chapter 8: Memory-Management Management Strategies Program must be brought into memory and placed within a process for it to be run Input queue collection of
More informationChapter 8: Memory Management Strategies
Chapter 8: Memory- Management Strategies, Silberschatz, Galvin and Gagne 2009 Chapter 8: Memory Management Strategies Background Swapping Contiguous Memory Allocation Paging Structure of the Page Table
More informationChapter 8: Memory Management. Background Swapping Contiguous Allocation Paging Segmentation Segmentation with Paging
Chapter 8: Memory Management Background Swapping Contiguous Allocation Paging Segmentation Segmentation with Paging 1 Background Memory management is crucial in better utilizing one of the most important
More informationChapter 8: Main Memory
Chapter 8: Main Memory Operating System Concepts 8 th Edition,! Silberschatz, Galvin and Gagne 2009! Chapter 8: Memory Management Background" Swapping " Contiguous Memory Allocation" Paging" Structure
More informationChapter 8: Main Memory
Chapter 8: Main Memory Chapter 8: Memory Management Background Swapping Contiguous Memory Allocation Paging Structure of the Page Table Segmentation Example: The Intel Pentium 8.2 Silberschatz, Galvin
More informationCS370 Operating Systems
CS370 Operating Systems Colorado State University Yashwant K Malaiya Spring 2018 L17 Main Memory Slides based on Text by Silberschatz, Galvin, Gagne Various sources 1 1 FAQ Was Great Dijkstra a magician?
More informationChapter 8: Memory Management
Chapter 8: Memory Management Chapter 8: Memory Management Background Swapping Contiguous Allocation Paging Segmentation Segmentation with Paging 8.2 Background Program must be brought into memory and placed
More informationI.-C. Lin, Assistant Professor. Textbook: Operating System Principles 7ed CHAPTER 8: MEMORY
I.-C. Lin, Assistant Professor. Textbook: Operating System Principles 7ed CHAPTER 8: MEMORY MANAGEMENT Chapter 8: Memory Management Background Swapping Contiguous Memory Allocation Paging Structure of
More informationAddresses in the source program are generally symbolic. A compiler will typically bind these symbolic addresses to re-locatable addresses.
1 Memory Management Address Binding The normal procedures is to select one of the processes in the input queue and to load that process into memory. As the process executed, it accesses instructions and
More informationI.-C. Lin, Assistant Professor. Textbook: Operating System Concepts 8ed CHAPTER 8: MEMORY
I.-C. Lin, Assistant Professor. Textbook: Operating System Concepts 8ed CHAPTER 8: MEMORY MANAGEMENT Chapter 8: Memory Management Background Swapping Contiguous Memory Allocation Paging Structure of the
More informationMemory Management. Memory Management
Memory Management Gordon College Stephen Brinton Memory Management Background Swapping Contiguous Allocation Paging Segmentation Segmentation with Paging 1 Background Program must be brought into memory
More informationFinal Review Spring 2018 Also see Midterm Review
Final Review Spring 2018 Also see Midterm Review CS370 Operating Systems Yashwant K Malaiya 1 1 Deadlocks System Model Resource allocation graph, claim graph (for avoidance) Deadlock Characterization Conditions
More informationGoals of Memory Management
Memory Management Goals of Memory Management Allocate available memory efficiently to multiple processes Main functions Allocate memory to processes when needed Keep track of what memory is used and what
More informationPrinciples of Operating Systems
Principles of Operating Systems Lecture 18-20 - Main Memory Ardalan Amiri Sani (ardalan@uci.edu) [lecture slides contains some content adapted from previous slides by Prof. Nalini Venkatasubramanian, and
More informationICS Principles of Operating Systems
ICS 143 - Principles of Operating Systems Lectures 17-20 - FileSystem Interface and Implementation Prof. Ardalan Amiri Sani Prof. Nalini Venkatasubramanian ardalan@ics.uci.edu nalini@ics.uci.edu Outline
More informationChapter 8: Memory- Manage g me m nt n S tra r t a e t gie i s
Chapter 8: Memory- Management Strategies Chapter 8: Memory Management Background Swapping Contiguous Memory Allocation Paging Structure of the Page Table Segmentation Example: The Intel Pentium 2009/12/16
More informationChapter 8: Memory- Management Strategies. Operating System Concepts 9 th Edition
Chapter 8: Memory- Management Strategies Operating System Concepts 9 th Edition Silberschatz, Galvin and Gagne 2013 Chapter 8: Memory Management Strategies Background Swapping Contiguous Memory Allocation
More informationCS307: Operating Systems
CS307: Operating Systems Chentao Wu 吴晨涛 Associate Professor Dept. of Computer Science and Engineering Shanghai Jiao Tong University SEIEE Building 3-513 wuct@cs.sjtu.edu.cn Download Lectures ftp://public.sjtu.edu.cn
More informationChapter 7: Main Memory. Operating System Concepts Essentials 8 th Edition
Chapter 7: Main Memory Operating System Concepts Essentials 8 th Edition Silberschatz, Galvin and Gagne 2011 Chapter 7: Memory Management Background Swapping Contiguous Memory Allocation Paging Structure
More informationMemory management. Last modified: Adaptation of Silberschatz, Galvin, Gagne slides for the textbook Applied Operating Systems Concepts
Memory management Last modified: 26.04.2016 1 Contents Background Logical and physical address spaces; address binding Overlaying, swapping Contiguous Memory Allocation Segmentation Paging Structure of
More informationPrinciples of Operating Systems
Principles of Operating Systems Lecture 21-23 - Virtual Memory Ardalan Amiri Sani (ardalan@uci.edu) [lecture slides contains some content adapted from previous slides by Prof. Nalini Venkatasubramanian,
More informationChapter 8: Main Memory
Chapter 8: Main Memory Chapter 8: Memory Management Background Swapping Contiguous Memory Allocation Segmentation Paging Structure of the Page Table Example: The Intel 32 and 64-bit Architectures Example:
More informationECE 7650 Scalable and Secure Internet Services and Architecture ---- A Systems Perspective. Part I: Operating system overview: Memory Management
ECE 7650 Scalable and Secure Internet Services and Architecture ---- A Systems Perspective Part I: Operating system overview: Memory Management 1 Hardware background The role of primary memory Program
More informationstack Two-dimensional logical addresses Fixed Allocation Binary Page Table
Question # 1 of 10 ( Start time: 07:24:13 AM ) Total Marks: 1 LRU page replacement algorithm can be implemented by counter stack linked list all of the given options Question # 2 of 10 ( Start time: 07:25:28
More informationChapter 8: Memory-Management Strategies
Chapter 8: Memory-Management Strategies Chapter 8: Memory Management Strategies Background Swapping Contiguous Memory Allocation Segmentation Paging Structure of the Page Table Example: The Intel 32 and
More informationCHAPTER 8: MEMORY MANAGEMENT. By I-Chen Lin Textbook: Operating System Concepts 9th Ed.
CHAPTER 8: MEMORY MANAGEMENT By I-Chen Lin Textbook: Operating System Concepts 9th Ed. Chapter 8: Memory Management Background Swapping Contiguous Memory Allocation Segmentation Paging Structure of the
More informationChapter 9 Memory Management Main Memory Operating system concepts. Sixth Edition. Silberschatz, Galvin, and Gagne 8.1
Chapter 9 Memory Management Main Memory Operating system concepts. Sixth Edition. Silberschatz, Galvin, and Gagne 8.1 Chapter 9: Memory Management Background Swapping Contiguous Memory Allocation Segmentation
More informationModule 3. DEADLOCK AND STARVATION
This document can be downloaded from www.chetanahegde.in with most recent updates. 1 Module 3. DEADLOCK AND STARVATION 3.1 PRINCIPLES OF DEADLOCK Deadlock can be defined as the permanent blocking of a
More informationCHAPTER 8 - MEMORY MANAGEMENT STRATEGIES
CHAPTER 8 - MEMORY MANAGEMENT STRATEGIES OBJECTIVES Detailed description of various ways of organizing memory hardware Various memory-management techniques, including paging and segmentation To provide
More informationCS307 Operating Systems Main Memory
CS307 Main Memory Fan Wu Department of Computer Science and Engineering Shanghai Jiao Tong University Spring 2018 Background Program must be brought (from disk) into memory and placed within a process
More informationChapter 8: Main Memory. Operating System Concepts 9 th Edition
Chapter 8: Main Memory Silberschatz, Galvin and Gagne 2013 Chapter 8: Memory Management Background Swapping Contiguous Memory Allocation Segmentation Paging Structure of the Page Table Example: The Intel
More informationChapter 8: Main Memory
Chapter 8: Main Memory Silberschatz, Galvin and Gagne 2013 Chapter 8: Memory Management Background Swapping Contiguous Memory Allocation Segmentation Paging Structure of the Page Table Example: The Intel
More informationMemory Management. Contents: Memory Management. How to generate code? Background
TDIU11 Operating systems Contents: Memory Management Memory Management [SGG7/8/9] Chapter 8 Background Relocation Dynamic loading and linking Swapping Contiguous Allocation Paging Segmentation Copyright
More informationCS6401- Operating System UNIT-III STORAGE MANAGEMENT
UNIT-III STORAGE MANAGEMENT Memory Management: Background In general, to rum a program, it must be brought into memory. Input queue collection of processes on the disk that are waiting to be brought into
More informationLecture 8 Memory Management Strategies (chapter 8)
Bilkent University Department of Computer Engineering CS342 Operating Systems Lecture 8 Memory Management Strategies (chapter 8) Dr. İbrahim Körpeoğlu http://www.cs.bilkent.edu.tr/~korpe 1 References The
More informationBasic Memory Management
Basic Memory Management CS 256/456 Dept. of Computer Science, University of Rochester 10/15/14 CSC 2/456 1 Basic Memory Management Program must be brought into memory and placed within a process for it
More informationChapters 9 & 10: Memory Management and Virtual Memory
Chapters 9 & 10: Memory Management and Virtual Memory Important concepts (for final, projects, papers) addressing: physical/absolute, logical/relative/virtual overlays swapping and paging memory protection
More informationChapter 8: Memory- Management Strategies. Operating System Concepts 9 th Edition
Chapter 8: Memory- Management Strategies Operating System Concepts 9 th Edition Silberschatz, Galvin and Gagne 2013 Chapter 8: Memory Management Strategies Background Swapping Contiguous Memory Allocation
More informationChapter 8: Memory- Management Strategies
Chapter 8: Memory Management Strategies Chapter 8: Memory- Management Strategies Background Swapping Contiguous Memory Allocation Segmentation Paging Structure of the Page Table Example: The Intel 32 and
More informationPerformance of Various Levels of Storage. Movement between levels of storage hierarchy can be explicit or implicit
Memory Management All data in memory before and after processing All instructions in memory in order to execute Memory management determines what is to be in memory Memory management activities Keeping
More information6 - Main Memory EECE 315 (101) ECE UBC 2013 W2
6 - Main Memory EECE 315 (101) ECE UBC 2013 W2 Acknowledgement: This set of slides is partly based on the PPTs provided by the Wiley s companion website (including textbook images, when not explicitly
More informationChapter 8 Main Memory
Chapter 8 Main Memory 8.1, 8.2, 8.3, 8.4, 8.5 Chapter 9 Virtual memory 9.1, 9.2, 9.3 https://www.akkadia.org/drepper/cpumemory.pdf Images from Silberschatz Pacific University 1 How does the OS manage memory?
More informationBasic Memory Management. Basic Memory Management. Address Binding. Running a user program. Operating Systems 10/14/2018 CSC 256/456 1
Basic Memory Management Program must be brought into memory and placed within a process for it to be run Basic Memory Management CS 256/456 Dept. of Computer Science, University of Rochester Mono-programming
More informationChapter 8 Memory Management
Chapter 8 Memory Management Da-Wei Chang CSIE.NCKU Source: Abraham Silberschatz, Peter B. Galvin, and Greg Gagne, "Operating System Concepts", 9th Edition, Wiley. 1 Outline Background Swapping Contiguous
More informationChapter 9: Virtual-Memory
Chapter 9: Virtual-Memory Management Chapter 9: Virtual-Memory Management Background Demand Paging Page Replacement Allocation of Frames Thrashing Other Considerations Silberschatz, Galvin and Gagne 2013
More informationMemory Management. Dr. Yingwu Zhu
Memory Management Dr. Yingwu Zhu Big picture Main memory is a resource A process/thread is being executing, the instructions & data must be in memory Assumption: Main memory is super big to hold a program
More informationBackground Swapping Contiguous Memory Allocation Paging Structure of the Page Table Segmentation
Background Swapping Contiguous Memory Allocation Paging Structure of the Page Table Segmentation Basic Hardware Address Binding Logical VS Physical Address Space Dynamic Loading Dynamic Linking and Shared
More informationRoadmap. Tevfik Koşar. CSC Operating Systems Spring Lecture - XII Main Memory - II. Louisiana State University
CSC 4103 - Operating Systems Spring 2007 Lecture - XII Main Memory - II Tevfik Koşar Louisiana State University March 8 th, 2007 1 Roadmap Dynamic Loading & Linking Contiguous Memory Allocation Fragmentation
More informationChapter 9 Memory Management
Contents 1. Introduction 2. Computer-System Structures 3. Operating-System Structures 4. Processes 5. Threads 6. CPU Scheduling 7. Process Synchronization 8. Deadlocks 9. Memory Management 10. Virtual
More informationChapter 8 & Chapter 9 Main Memory & Virtual Memory
Chapter 8 & Chapter 9 Main Memory & Virtual Memory 1. Various ways of organizing memory hardware. 2. Memory-management techniques: 1. Paging 2. Segmentation. Introduction Memory consists of a large array
More informationCS450/550 Operating Systems
CS450/550 Operating Systems Lecture 4 memory Palden Lama Department of Computer Science CS450/550 Memory.1 Review: Summary of Chapter 3 Deadlocks and its modeling Deadlock detection Deadlock recovery Deadlock
More informationMemory Management. Reading: Silberschatz chapter 9 Reading: Stallings. chapter 7 EEL 358
Memory Management Reading: Silberschatz chapter 9 Reading: Stallings chapter 7 1 Outline Background Issues in Memory Management Logical Vs Physical address, MMU Dynamic Loading Memory Partitioning Placement
More informationOperating Systems. No. 9 ศร ณย อ นทโกส ม Sarun Intakosum
Operating Systems No. 9 ศร ณย อ นทโกส ม Sarun Intakosum 1 Virtual-Memory Management 2 Background Virtual memory separation of user logical memory from physical memory. Only part of the program needs to
More informationMemory Management. Dr. Yingwu Zhu
Memory Management Dr. Yingwu Zhu Big picture Main memory is a resource A process/thread is being executing, the instructions & data must be in memory Assumption: Main memory is infinite Allocation of memory
More informationOperating Systems. Memory Management. Lecture 9 Michael O Boyle
Operating Systems Memory Management Lecture 9 Michael O Boyle 1 Memory Management Background Logical/Virtual Address Space vs Physical Address Space Swapping Contiguous Memory Allocation Segmentation Goals
More informationMain Memory. CISC3595, Spring 2015 X. Zhang Fordham University
Main Memory CISC3595, Spring 2015 X. Zhang Fordham University 1 Memory Management! Background!! Contiguous Memory Allocation!! Paging!! Structure of the Page Table!! Segmentation!! Example: The Intel Pentium
More informationMain Memory. Electrical and Computer Engineering Stephen Kim ECE/IUPUI RTOS & APPS 1
Main Memory Electrical and Computer Engineering Stephen Kim (dskim@iupui.edu) ECE/IUPUI RTOS & APPS 1 Main Memory Background Swapping Contiguous allocation Paging Segmentation Segmentation with paging
More informationChapter 8: Memory Management
Chapter 8: Memory Management Chapter 8: Memory Management Background Swapping Contiguous Allocation Paging Segmentation Segmentation with Paging 8.2 Silberschatz, Galvin and Gagne 2005 Background Program/Code
More informationModule 9: Virtual Memory
Module 9: Virtual Memory Background Demand Paging Performance of Demand Paging Page Replacement Page-Replacement Algorithms Allocation of Frames Thrashing Other Considerations Demand Segmenation 9.1 Background
More informationMemory Management. Memory
Memory Management These slides are created by Dr. Huang of George Mason University. Students registered in Dr. Huang s courses at GMU can make a single machine readable copy and print a single copy of
More informationMemory Management. Chapter 4 Memory Management. Multiprogramming with Fixed Partitions. Ideally programmers want memory that is.
Chapter 4 Memory Management Ideally programmers want memory that is Memory Management large fast non volatile 4.1 Basic memory management 4.2 Swapping 4.3 Virtual memory 4.4 Page replacement algorithms
More informationCS 3733 Operating Systems:
CS 3733 Operating Systems: Topics: Memory Management (SGG, Chapter 08) Instructor: Dr Dakai Zhu Department of Computer Science @ UTSA 1 Reminders Assignment 2: extended to Monday (March 5th) midnight:
More informationICS Principles of Operating Systems. Lectures Set 5- Deadlocks Prof. Nalini Venkatasubramanian
ICS 143 - Principles of Operating Systems Lectures Set 5- Deadlocks Prof. Nalini Venkatasubramanian nalini@ics.uci.edu Outline System Model Deadlock Characterization Methods for handling deadlocks Deadlock
More informationAdministrivia. Deadlock Prevention Techniques. Handling Deadlock. Deadlock Avoidance
Administrivia Project discussion? Last time Wrapped up deadlock Today: Start memory management SUNY-BINGHAMTON CS35 SPRING 8 LEC. #13 1 Handling Deadlock Deadlock Prevention Techniques Prevent hold and
More informationSHANDONG UNIVERSITY 1
Chapter 8 Main Memory SHANDONG UNIVERSITY 1 Contents Background Swapping Contiguous Memory Allocation Paging Structure of the Page Table Segmentation Example: The Intel Pentium SHANDONG UNIVERSITY 2 Objectives
More informationLast Class: Deadlocks. Where we are in the course
Last Class: Deadlocks Necessary conditions for deadlock: Mutual exclusion Hold and wait No preemption Circular wait Ways of handling deadlock Deadlock detection and recovery Deadlock prevention Deadlock
More informationCS420: Operating Systems
Main Memory James Moscola Department of Engineering & Computer Science York College of Pennsylvania Based on Operating System Concepts, 9th Edition by Silberschatz, Galvin, Gagne Background Program must
More informationB. V. Patel Institute of Business Management, Computer &Information Technology, UTU
BCA-3 rd Semester 030010304-Fundamentals Of Operating Systems Unit: 1 Introduction Short Answer Questions : 1. State two ways of process communication. 2. State any two uses of operating system according
More informationFile Systems. OS Overview I/O. Swap. Management. Operations CPU. Hard Drive. Management. Memory. Hard Drive. CSI3131 Topics. Structure.
File Systems I/O Management Hard Drive Management Virtual Memory Swap Memory Management Storage and I/O Introduction CSI3131 Topics Process Management Computing Systems Memory CPU Peripherals Processes
More informationMemory Management and Protection
Part IV Memory Management and Protection Sadeghi, Cubaleska RUB 2008-09 Course Operating System Security Memory Management and Protection Main Memory Virtual Memory Roadmap of Chapter 4 Main Memory Background
More informationModule 9: Virtual Memory
Module 9: Virtual Memory Background Demand Paging Performance of Demand Paging Page Replacement Page-Replacement Algorithms Allocation of Frames Thrashing Other Considerations Demand Segmentation Operating
More informationCSE 4/521 Introduction to Operating Systems. Lecture 27 (Final Exam Review) Summer 2018
CSE 4/521 Introduction to Operating Systems Lecture 27 (Final Exam Review) Summer 2018 Overview Objective: Revise topics and questions for the final-exam. 1. Main Memory 2. Virtual Memory 3. Mass Storage
More informationOperating Systems. Designed and Presented by Dr. Ayman Elshenawy Elsefy
Operating Systems Designed and Presented by Dr. Ayman Elshenawy Elsefy Dept. of Systems & Computer Eng.. AL-AZHAR University Website : eaymanelshenawy.wordpress.com Email : eaymanelshenawy@yahoo.com Reference
More informationCSE325 Principles of Operating Systems. Virtual Memory. David P. Duggan. March 7, 2013
CSE325 Principles of Operating Systems Virtual Memory David P. Duggan dduggan@sandia.gov March 7, 2013 Reading Assignment 9 Chapters 10 & 11 File Systems, due 3/21 3/7/13 CSE325 - Virtual Memory 2 Outline
More informationPrinciples of Operating Systems
Principles of Operating Systems Lecture 24-26 - File-System Interface and Implementation Ardalan Amiri Sani (ardalan@uci.edu) [lecture slides contains some content adapted from previous slides by Prof.
More informationPage Replacement. 3/9/07 CSE 30341: Operating Systems Principles
Page Replacement page 1 Page Replacement Algorithms Want lowest page-fault rate Evaluate algorithm by running it on a particular string of memory references (reference string) and computing the number
More informationChapter 8: Main Memory. Operating System Concepts 8th Edition
Chapter 8: Main Memory Operating System Concepts 8th Edition Silberschatz, Galvin and Gagne 2009 Chapter 8: Memory Management Background Swapping Contiguous Memory Allocation Paging Structure of the Page
More informationChapter 4 Memory Management
Chapter 4 Memory Management 4.1 Basic memory management 4.2 Swapping 4.3 Virtual memory 4.4 Page replacement algorithms 4.5 Modeling page replacement algorithms 4.6 Design issues for paging systems 4.7
More informationVirtual Memory Outline
Virtual Memory Outline Background Demand Paging Copy-on-Write Page Replacement Allocation of Frames Thrashing Memory-Mapped Files Allocating Kernel Memory Other Considerations Operating-System Examples
More informationOperating System 1 (ECS-501)
Operating System 1 (ECS-501) Unit- IV Memory Management 1.1 Bare Machine: 1.1.1 Introduction: It has the ability to recover the operating system of a machine to the identical state it was at a given point
More informationOptimal Algorithm. Replace page that will not be used for longest period of time Used for measuring how well your algorithm performs
Optimal Algorithm Replace page that will not be used for longest period of time Used for measuring how well your algorithm performs page 1 Least Recently Used (LRU) Algorithm Reference string: 1, 2, 3,
More informationThe Memory Management Unit. Operating Systems. Autumn CS4023
Operating Systems Autumn 2017-2018 Outline The Memory Management Unit 1 The Memory Management Unit Logical vs. Physical Address Space The concept of a logical address space that is bound to a separate
More informationBackground. Demand Paging. valid-invalid bit. Tevfik Koşar. CSC Operating Systems Spring 2007
CSC 0 - Operating Systems Spring 007 Lecture - XIII Virtual Memory Tevfik Koşar Background Virtual memory separation of user logical memory from physical memory. Only part of the program needs to be in
More informationBackground. Contiguous Memory Allocation
Operating System Lecture 8 2017.5.9 Chapter 8 (Main Memory) Background Swapping Contiguous Memory Allocation Segmentation - Paging Memory Management Selection of a memory-management method for a specific
More informationMain Memory (Part I)
Main Memory (Part I) Amir H. Payberah amir@sics.se Amirkabir University of Technology (Tehran Polytechnic) Amir H. Payberah (Tehran Polytechnic) Main Memory 1393/8/5 1 / 47 Motivation and Background Amir
More informationChapter 9: Virtual Memory
Chapter 9: Virtual Memory Chapter 9: Virtual Memory 9.1 Background 9.2 Demand Paging 9.3 Copy-on-Write 9.4 Page Replacement 9.5 Allocation of Frames 9.6 Thrashing 9.7 Memory-Mapped Files 9.8 Allocating
More informationOperating Systems Unit 6. Memory Management
Unit 6 Memory Management Structure 6.1 Introduction Objectives 6.2 Logical versus Physical Address Space 6.3 Swapping 6.4 Contiguous Allocation Single partition Allocation Multiple Partition Allocation
More information